In the prior art, as FIGS. 1 to 4 show, a raised pattern is provided around ports 11 (fluid inlet and fluid outlet) of a heat exchange plate of a plate-type heat exchanger, to increase the strength of the plate-type heat exchanger and cause a larger pressure drop between the port 11 and a fluid channel, and thereby achieve better fluid distribution between fluid channels. With regard to the structural design of existing products, since the strength is low, it is necessary to make the plates relatively thick to increase strength, so costs are high.
As FIG. 1 shows, existing raised patterns include a spider's web design, but such a raised pattern has low strength under certain conditions, and the layout is determined by a fish bone pattern of a heat exchange part.
As FIG. 2 shows, the raised pattern shown in FIG. 2 is not limited by the pattern of the heat exchange part, but the protrusions are independent, so in certain situations, strength is low.
The raised pattern shown in FIG. 3 is formed by cutting away a part of long protrusions; this raised pattern has low strength, and poor manufacturability.
In addition, when the raised pattern formed by long protrusions shown in FIG. 4 is employed, the strength of the plate-type heat exchanger is low, and stresses are not borne uniformly.
In the various types of structure above, there must be a section of plane flush with a basic plane between every two adjacent protrusions, i.e. a transitional part between two adjacent protrusion points is a lower plane. As a result, the distance between every two protrusions cannot be too small, so strength is limited and restrictions are increased.